A problem with file caching over networks such as the Internet is that files are sometimes needlessly re-transmitted from a central-repository file server to one or more peripheral file caching servers. Unnecessary file re-transmission usually occurs when a single file has two or more names by which it can be requested or stored. A client computer's request for a copy of the file to a file caching server using one name can cause the file caching server to needlessly request the file from a central file server if the file caching server already has a copy of the requested file, albeit under a different name or version.
A further problem with data caching is the time wasted to needlessly retrieve files from the file server 24 to the file caching server 10 when one or more of the clients 14 require resources from the file server 24 which might already be available on the file caching server 10, especially when using a slow speed or limited bandwidth connection 22 between computer systems. When a file, web page or other data object is requested from the file server 24 the requested item might be retrievable using different file names, web page URLs, or other identifiers resulting in unnecessary file transfers between the file server 24 and the caching server 10.
Another problem with prior art file storage is the redundant storage under different file names of files that contain identical data. This can particularly be a problem in the context of file storage associated with the backup of files from many computers. In this context, a large number of computers may have files identical to the files on many of the other computers. A file storage device used for file backup of many computers may therefore store many copies of identical files having different names.